Conveying systems and methods of use

ABSTRACT

The present invention provides an improved conveyor system that provides for a magnetically driven conveyor system in which a sidewall of the conveyor may have minimal or no perforations therein for connecting rollers or other conveying structures in the conveyor bed to an external driving mechanism. The conveyor system may also provide gapless or nearly gapless roller bed that prevents or reduces the accumulation of debris and contaminants in and between the hardware of the conveyor bed. The system of the present invention may provide a more efficient and sanitary conveyor system for produce washing or other food processing application that requires less maintenance.

This application claims the benefit of U.S. Provisional PatentApplication No. 62/127,197 filed on Mar. 2, 2015, and U.S. patentapplication Ser. No. 15/055,254 filed on Feb. 26, 2016, both of whichare incorporated herein by this reference in their entireties.

FIELD OF THE INVENTION

The present invention relates to novel conveyor systems, and moreparticularly to roller conveyor systems employing a magnetic rotorsystem for rotating the rollers while preventing contamination of theconveyor system, and methods of using the same.

DISCUSSION OF THE BACKGROUND

A wide variety of conveyor systems have been developed for use intransporting produce during harvest, cleaning, and packaging. Rollerconveyors are commonly used in such applications. Roller conveyors maybe used, for example, in produce washing tables, which may include a setof rollers having bristles thereon for contacting the fruit, a retainingwall along the lateral sides of the table to prevent the produce fromfalling off of the washing table, and a roller driving system thatengages the rollers to cause them to convey the produce through thesystem.

Roller conveyors used to convey articles along a given pathway aregenerally comprised of plurality of spaced, parallel rollers positionedalong and transverse to the pathway. A frame having parallel rollersupport sections typically supports the rollers. Each roller typicallyhas a shaft or axle that is supported at its opposed ends by the framesupport sections. A roller body is provided on each shaft to support thearticle being conveyed (e.g., produce). A typical conveyor frameincludes a pair of spaced, parallel side rails each having a verticalwall with an inner face and an outer face. A plurality of openings aretypically provided on each side rail to support the roller shafts, withthe openings on one side rail mirroring the openings in the other siderail. The side rails may also be configured to further isolate the drivemeans from the rollers, e.g., with an upper wall extending outwardlyfrom the upper edge of the vertical wall.

In conventional roller conveyor systems, shafts extend out from bothends of each roller. These shafts are typically supported by theopenings in the side rails, and the roller shafts extend throughopenings in the side rails. The shafts on one side of these systems aresimply allowed to idly rotate in place in the openings, while the shaftson the other side extend through the side rail openings where they areengaged to a driving motor through a transmission system.

Conventional roller conveyor systems for a produce washing tables andother systems typically utilize a sprocket system, in which each rolleris connected to a sprocket through the retaining wall by a mechanicalcoupling assembly. It is to be appreciated that the openings in the siderails must be present in order to connect the rollers to the drivingmechanism through the mechanical coupling assembly. Unfortunately, thegaps between the rollers and the retaining walls and the openingsthrough the side rails allow the passage of water, cleaning solutions,wax, debris, and other materials. These contaminants may pass from theroller bed through the retaining wall and into the drive system, whichmay clog or damage the system, requiring cleaning and repair.Conversely, foreign materials may pass into the system and onto therollers from the outside, potentially contaminating the fruit or otherproduct being conveyed thereon.

Importantly, any gaps between the lateral ends of the rollers and theretaining walls of the conveyor, as well as the holes in the side rails,may act as a collection site for debris and bacteria, which can resultin contamination of the produce on the washing table. In some systems,rubber seals or bearings may be provided in the shaft support side wallopenings to prevent such contamination, but these may only serve tocollect and accumulate undesirable contaminants from the conveyedproducts. Regular cleaning is therefore necessary to maintain a safefood processing environment and minimize the threat of contamination byharmful microbes such as safe and free of any contaminants such as E.coli and Listeria. Proper cleaning may be onerous and costly to theoperator in terms of both labor and down time.

In particular, it is often necessary to disassemble these conveyorsystems for effective and thorough cleaning. The disassembly process canbe time-consuming and tedious because it may be necessary to disassemblethe roller bed and the drive mechanism in order to sufficiently accessthe interior parts of the conveying system for sanitation andmaintenance. The rollers may need to be removed from their mountings onthe conveyor system in order to access the surfaces of the roller, theretaining wall and the coupling assembly, where debris may accumulate.Conveyor system drive mechanism components must be thoroughly cleaned ona regular basis to both maintain the conveyor system in proper workingorder and to prevent bacteria, foreign particulates or othercontamination from coming in contact with the food products.

The time required to disassemble and clean and/or repair a conveyorsystem can result in a loss of production time while the conveyor systemis inoperable and a corresponding loss of revenues. Additionally, thedrive system and other components may be damaged over time by thecontinuous accumulation of materials from the roller bed. It istherefore desirable to provide a conveyor system that reduces the riskof debris accumulation in the mechanical system and prevents or reducescontamination of the system.

Unfortunately, experience has shown that even regular and thoroughcleaning of produce conveyor systems is often not enough to eradicate E.coli and Listeria because these pathogens are capable of surviving ineven the smallest and most remote areas. Because of the potential forcontamination of produce on the rollers, and because of the potentialfor transmission of contaminants from the conveyor rollers to the drivemechanism and vice versa, it is desirable to minimize the number ofplaces where such contaminants may be transmitted or accumulate.

It is therefore desirable to provide a novel conveyor system thataddresses such issues.

SUMMARY OF THE INVENTION

The present invention relates to improved conveyor systems and moreparticularly to improved conveyor systems that utilize a magnetic rotorsystem that may prevent the passage of debris and contaminants out ofthe conveyor bed into other parts of the machine, including the drivingsystem, and/or allows the gap between rollers and retaining walls(sidewalls) along the conveyor bed to be minimized, and methods of usingthe same. In some embodiments, the conveyor systems may be configured tohandle produce at various stages of processing while minimizing thedebris and contaminants collected by the conveyor bed components (e.g.,brush rollers) and the collection of debris in and on the driving systemof the conveyor. In this manner, damage and wear on the driving systemof the conveyor may be prevented and the collection of bacteria, fungus,and other contaminants at the sidewalls of the roller bed may beminimized, thereby reducing the time and frequency of conveyormaintenance procedures.

Other embodiments of the present invention may be utilized for otherindustrial and manufacturing applications. For example, and withoutlimitation, the roller conveyor systems of the present invention may beused for routing isolated loads (pallets, containers, boxes, cartons,etc.) in the areas of rail and air freight in-feed, automatic postalpackage sorting, hospital logistics, medical device and pharmaceuticalmanufacturing, transport and storage of documents and files, transfer ofelectronics on assembly line, routing of orders to a shipping point,sorting of cartons, weighing and labeling stations, food productpackaging line (deep-frozen foods), handling of bags and containers,reception of pallets (docks), preparation of orders for mail ordersales, and other industrial and manufacturing applications.

The conveyor systems of the present invention may include a conveyor bedin which the rollers are positioned, lateral sidewalls for preventingitems from falling off of the conveyor bed, at least one driving systemfor driving a driving chain or belt connected to sprocket and bearingassemblies, magnetic driving rotors connected to the sprocket andbearing assemblies, and the rotation of the rollers fitted with passivemagnetic rotors to magnetically engage the magnetic driving rotorsthrough the sidewall. However, the present invention is not limited tothis particular arrangement. For example, the magnetic driving rotorsmay be electromagnetic rotors that include one or more electromagnetsthat alternate their polarity to drive the rotation of the passivemagnetic rotors on the opposite side of the sidewall. In furthervariations, each magnetic driving rotor may be engaged with a separatemotor (e.g., an AC motor, etc.) driving the rotation of the magneticrotor. Still further variations on the driving system of the presentinvention are within the scope of the present invention, and arediscussed herein.

In some embodiments, and without limitation, the passive magnetic rotorsmay be supported/suspended on one lateral side by the magnetic drivingrotors, without any pin or axle engaging with the sidewall or themagnetic driving rotors. In such embodiments, the sidewall may have noopenings or holes at or near the level of the rollers (e.g., whereliquid and debris may be present) that would allow the passage of debrisand contaminants from the roller bed to the driving system on the otherside of the sidewall. In other embodiments, and without limitation, therollers may each have a pin or axle that sits in a recess in thesidewall (e.g., a recess that does not traverse the entire thickness ofthe sidewall), such that the pin or axle aids in suspending andmaintaining the position of the roller in the roller bed. In stillfurther embodiments, and without limitation, the rollers may each have apin or axle that sits in an opening in the sidewall. In suchembodiments, without limitation, the opening may have a minimal diameter(e.g., the pin or axle may have a tapered and/or reduced diameter whereit meets the hole to accommodate a smaller diameter hole). In suchembodiments, a gasket or grommet (e.g., a low friction grommet) may bepositioned between the pin or axle and the opening or hole in thesidewall to reduce or eliminate any gap between the axle or pin and theperimeter of the hole and to prevent the collection or passage of debrisor contaminants in the hole.

The passive magnetic rotors (which are integral to or engaged with therollers) may sit tightly against the interior side of the sidewalls suchthat the gap between the roller and the sidewall is minimized, therebyreducing or preventing the accumulation of debris and contaminantsbetween the roller and the sidewall. The system may also include agasket between the passive magnetic rotors and the sidewall to furtherblock and reduce the accumulation of any debris between the roller andthe sidewall. For example, and without limitation, the gasket may becircular and be positioned along the perimeter of the face of thepassive magnetic rotor.

The rollers may be made from plastic, steel, aluminum, or othermaterials, and may include surface features thereon, such as rubbercoating to create friction between the conveyed items and the rollers.In some embodiments, and without limitation, the surface of the rollersmay include pegs, bristles, and/or other structures for grasping theconveyed items. In some embodiments, and without limitation, the rollersmay have a water-proof surface (e.g., for a produce wash table or otherimplementation that utilizes water or other liquids), such as arubberized coating. In some embodiments, and without limitation, therollers may include an anti-microbial surface treatment or surfacematerials, such as a layer comprising copper or other antimicrobialmaterial.

In some embodiments, and without limitation, in the operational statethe rollers are indirectly driven by a driving system positioned outsideof the sidewalls of the conveyor bed. In some embodiments, and withoutlimitation, the driving system may include a motor and a transmissionassembly that connects the motor to a plurality of rotary shafts anddrives the rotary shafts in a uniform direction. The motor may be any ofvarious kinds of motors (e.g., an AC motor, a servo motor, etc.) and thetransmission assembly may include a chain (e.g., a roller chain, silentchain, etc.) or belt (e.g., a toothed belt, V-belt, etc.) and a seriesof sprockets, where the sprockets are connected to the motor by thechain or belt, which may drive rotation of the sprockets as the motorspins. The sprockets, in turn, may be connected directly or indirectlyto the magnetic driving rotors. For example, and without limitation, thesprockets may be connected to the magnetic driving rotors via a commonaxle. In other examples, and without limitation, the sprocket may becoupled directly to the magnetic driving rotors by a coupling or joint.The assembly of the sprockets and magnetic driving rotors may bepositioned on the exterior of the conveyor bed, for example, on theouter side of one of the sidewalls. The magnetic driving rotors may bepositioned near or at an outside surface of one of the sidewalls, suchthat they may be magnetically coupled to the passive magnetic rotors onthe opposite side of the sidewall. The sidewall may be made from anon-magnetic, rigid, and sturdy material (e.g., stainless steel,aluminum, polymer, composite, etc.).

The motor may be in electronic communication with a controller. Thecontroller may have analog or digital controls for turning the motor onor off, and/or to set a rate at which the motor cycles the chain orbelt. In some examples, and without limitation, the controller may be inelectronic communication with a computer (e.g., a system having amicroprocessor), which may positioned at or near the conveyor bed or maybe remote and have a wired or wireless connection to the controller.Such a computer may include software capable of directing the controllerto signal the motor to cycle the chain or belt at various speeds.

In some embodiments, and without limitation, each of the magneticdriving rotors may be engaged with a separate motor. For example, eachmagnetic driving rotor may be connected to and driven by its own ACmotor, a servo motor, etc. The motors may be in electronic communicationwith a controller. The controller may have analog or digital controlsfor turning the motors on or off, and/or to set a rate at which themagnetic driving rotors spin. In some examples, and without limitation,the controller may be in electronic communication with a computer (e.g.,a system having a microprocessor), which may positioned at or near theconveyor bed or may be remote and have a wired or wireless connection tothe controller. Such a computer may include software capable ofdirecting the controller to signal the motors to drive rotation of thedriving rotors at various speeds.

The magnetic driving rotors may have various arrangements of magnetstherein. For example, and without limitation, the magnetic rotor mayhave a plurality of small magnets embedded in the surface thereof,wherein the magnets are arranged such that the polarity of adjacentmagnets alternates. The passive magnetic rotor may have a complementarypattern of magnets, such that as the magnetic driving rotor rotates, themagnets of the passive magnetic rotor stay aligned with the oppositelypoled magnets of the magnetic driving rotor. For example, the magnets ofthe passive magnetic rotors may be simultaneously attracted by theoppositely poled magnets of the magnetic driving rotor and repelled bythe adjacent like-poled magnets of the magnetic driving rotor, therebymaintaining the position passive magnetic rotor relative to thecorresponding magnetic driving rotor.

In other examples, and without limitation, the magnet driving rotor mayhave magnets arranged with polar orientation of the magnets all matching(e.g., the positive poles may all be facing outward from the face of themagnetic driving rotor), and the passive magnetic rotor may have itsmagnets arranged with matching polar orientations, such that they havethe opposite polarity to the magnets of the magnetic driving rotor andthe rotors are attracted to one another (e.g., the negative poles mayall be facing outward from the face of the passive rotor). In stillfurther examples, and without limitation, the magnet driving rotor mayhave magnets arranged with polar orientation of the magnets all matching(e.g., the positive poles may all be facing outward from the face of therotor), and the passive magnetic rotor may have its magnets arrangedwith matching polar orientations, such that they match the orientationof the magnets of the magnetic driving rotor and the rotors are repelledby one another (e.g., the positive poles may all be facing outward fromthe face of the rotor). In such examples, the passive magnetic rotor maybe suspended in the conveyor bed by a pin or rod engaged with a sidewallof the conveyor bed. In still further embodiments, and withoutlimitation, magnetic driving rotor may include two semicircular magnetsof opposite polarity running along the perimeter of the magnetic drivingrotor, and the passive magnetic rotor may have a complementaryarrangement of semicircular magnets, such that the magnets experiencethe same attraction and repulsion forces as described in the aboveexample. Various other arrangements of permanent magnets are alsocontemplated within the scope of the present invention.

Without limitation, the driving system may incorporate electromagnets insome embodiments of the present invention. For example, and withoutlimitation, rather than having a motor and a driving belt or chain, themagnets in the face of the driving magnetic rotor may be electromagnetsin electronic communication with an electronic controller (e.g., anelectronic control circuit having manual controls for a human operator,an electronic control circuit having a processor that controls thecurrent flowing to the electromagnets, etc.). The electronic controlcircuit may alternate the current applied to each electromagnet toalternate the polarity of each of the electromagnets in a coordinatedfashion. For example, the polarity of the magnets may be controlled suchthat adjacent magnets always have opposite polarities. Additionally, thepassive magnetic rotor may have permanent magnets arranged in a patternthat corresponds to the pattern of electromagnets in the magneticdriving rotor (e.g., the magnets may be about the same size and have acorresponding position in the passive rotor), where the permanentmagnets alternate in polarities such that adjacent magnets have oppositepolarities. In such a design, the alternating polarities of theelectromagnets may propel rotation of the passive rotor as thepolarities of each of the electromagnets cycle between positive andnegative in a coordinated alternating pattern. The speed of the rotationof the passive magnetic rotor (and the roller) may be controlled by thefrequency of the alternating current applied to the electromagnets. Theelectronic controller may have analog or digital controls for turningthe electromagnets on or off, and/or to set a rate at which theelectromagnets alternate their polarity. In some examples, and withoutlimitation, the controller may be in electronic communication with acomputer (e.g., a system having a microprocessor), which may positionedat or near the conveyor bed or may be remote and have a wired orwireless connection to the controller of the electromagnets. Such acomputer may include software capable of directing the controller tosignal the electromagnets to switch polarities at various rates and invarious patterns.

Other implementations of electromagnets are contemplated within thescope of the present invention as well. For example, and withoutlimitation, a driving system may include a motor and a driving chain orbelt that may be used with rotors that include electromagnets ofconstant polarity, rather than permanent magnets.

Without limiting the invention, the conveyor system may also include asweeping device or clean-out bar that may be used to periodically clearproduce or other items from the conveyor bed. The sweeping device may bea bar that can be passed closely over the rollers of the convey bed fromthe input end of the conveyor bed to the output end, drawing any produceor other items or materials out of the conveyor bed. Like the rollers ofthe conveyor system, the sweeping device may be connected to an exteriordriving mechanism. In some embodiments, and without limitation, theexterior driving mechanism may be connected to the sweeping device bymagnetic force across a sidewall of the conveyor bed. The sweepingdevice may include a driving system that may be on the exterior side ofone or both of the sidewalls of the system and a sweeping arm that isconnected to the driving system by magnetic force across the sidewall.For example, and without limitation, the conveyor system may have asweeping device motor (e.g., an AC motor, a servo motor, etc.) that isconnected to a sprocket that drives the rotation of a driving belt orchain. The driving belt or chain may be attached to a magnetic couplerthat is adjacent to the sidewall such that it can magnetically couple toa sweeping bar in the conveyor bed on the opposite side of the sidewall.As the driving belt or chain is advanced by the sprocket, it may drawthe sweeping bar along the conveyor bed.

The sweeping device motor may be in electronic communication with acontroller. The controller may have analog or digital controls forturning the motor on or off, and/or to set a rate at which the motorcycles the chain or belt. In some examples, and without limitation, thecontroller may be in electronic communication with a computer (e.g., asystem having a microprocessor), which may positioned at or near theconveyor bed or may be remote and have a wired or wireless connection tothe controller. Such a computer may include software capable ofdirecting the controller to signal the sweeping device motor to cyclethe driving chain or belt at various speeds. In some examples, a singlecomputer may be in electronic communication with the controller for thesweeping device motor and the controller for the one or more motors fordriving the magnetic driving rotors. In such examples, and withoutlimitation, such a computer may include software capable of (1)directing the controller of the sweeping device to signal the sweepingdevice motor to cycle the driving chain or belt at various speeds and(2) directing the one or more motors driving the magnetic driving rotorsto run at various speeds.

Other implementations and designs of the sweeping device arecontemplated within the scope of the present invention. For example, andwithout limitation, the sweeping bar may be attached through a sidewallof the conveyor bed directly to a driving belt or chain located on theouter side of the sidewall.

It is to be understood that there may be additional variations in thedesign of the conveying systems described herein. For example, andwithout limitation, the conveyor bed may have various linear, curved,and/or multi-directional conveying paths. Also, the conveying system ofthe present invention may be adapted to various industries and processesthat utilize roller conveyors. For example, the conveyor system of thepresent invention may include rollers that are spaced apart at apredetermined distance (along with other related adaptations) and/orhave gaps along their lengths (e.g., the rollers may consist of spacedparallel disks on an axle shaft) to function as a sizing table forproduce or other sizing applications. Other alterations and applicationsof the conveyor systems described herein are within the scope of thepresent invention.

In some embodiments, and without limitation, the present inventionrelates to a conveying assembly that includes a roller conveyor bedhaving a plurality of rollers held therein, sidewalls (retaining walls)positioned longitudinally along the conveyor bed to prevent produce orother items from falling off of the conveyor, at least one motor fordriving the rotation of the rollers, a plurality of sprocket and bearingassemblies (transmission assemblies) for driving the rollers, a drivingchain connecting the plurality of sprocket and bearing assemblies, aplurality of magnetic driving rotors for connection to the sprocket andbearing assemblies, and a plurality of passive magnetic rotors that maybe magnetically engaged with the magnetic driving rotors through thesidewall. Each of the plurality of passive magnetic rotors may beembedded in one of the rollers such that the passive magnetic rotors aretightly positioned in an end of the roller with little or no protrusionfrom the end of the roller. The passive magnetic rotors may sit flushagainst the interior side of the sidewall and a gap between outercircumference of the rollers (e.g., the brush portion) and the sidewallmay be minimized, thereby reducing accumulation of debris andcontaminants between the roller and the sidewall. The gap between eachof the rollers and the sidewall may be less than about 5 mm. Each of thepassive magnetic rotors may further include a gasket that sits betweenthe passive magnetic rotor and the sidewall, such that the gasketfurther block and prevent the accumulation of any debris between therollers and said sidewall.

The magnetic driving rotors may include a plurality of magnets arrangedin a first alternating polarity pattern around the axis of the magneticdriving rotor. The passive magnetic rotors may include a plurality ofmagnets arranged in a second alternating polarity pattern around theaxis of the passive magnetic rotor. The first alternating polaritypattern and the second alternating polarity pattern may be complementaryand may be aligned across the sidewall, such that each of the negativepoles in the first alternating polarity pattern is aligned with one ofthe positive poles in the second alternating polarity pattern and eachof the positive poles in the first alternating polarity pattern isaligned with one of the negative poles in the second alternatingpolarity pattern.

The conveying assembly may also include passive gears between each pairof adjacent sprockets, where the passive gears may be closer to thecommon plane on which the axes of the sprockets sit than the point alongthe outer circumference of the sprocket that is furthest from the commonplane. The driving chain may be routed around the sprockets and thepassive gears to create a sinusoidal path for the driving chain. Thedriving chain may be routed through the motor and the force generated bythe motor may be transferred through the driving chain to the sprockets.In some implementations, the motor may be attached to an axle of one ofthe plurality of sprocket and bearing assemblies, and the forcegenerated by the motor may be transferred through the axle to thedriving chain to the other sprockets in the plurality of sprocket andbearing assemblies.

In some embodiments, and without limitation, the present inventionrelates to a conveying assembly that includes a conveyor bed having asidewall, a plurality of rollers aligned in the conveyor bed on a firstside of a sidewall, each roller having a recess in an end thereof, aplurality of passive magnetic rotors, each embedded in the recess of oneof the plurality of rollers, and a plurality of magnetic driving rotorslocated on a second side of the sidewall for magnetically engaging theplurality of passive magnetic rollers across the sidewall, whererotation of the magnetic driving rotors drives the rotation of thepassive magnetic rotors. The passive magnetic rotors may be tightlyembedded in the recesses of the rollers with little or no protrusionfrom the end of the rollers. The passive magnetic rotors may sit flushagainst the interior side of the sidewall such that there is a minimalgap between the roller and the sidewall, thereby reducing accumulationof debris and contaminants between the roller and sidewall. The conveyorassembly may further include a gasket between each of the passivemagnetic rotors and the sidewall to further block and prevent theaccumulation of any debris between the rollers and the sidewall. Themagnetic driving rotors may include a plurality of magnets arranged in afirst alternating polarity pattern around the axis of the rotor. Thepassive magnetic rotors include a plurality of magnets arranged in asecond alternating polarity pattern around the axis rotor, where thesecond alternating polarity pattern is complementary to the firstalternating polarity pattern.

The assembly may further include a plurality of sprocket and bearingassemblies (transmission assemblies), a driving chain, and a motor,where each of the plurality of sprocket and bearing assemblies may befixedly connecting to one of the magnetic driving rotors, the drivingchain is connected to each of the sprockets, and the motor drives therotation of the chain. In other examples, the assembly may include aplurality of motors, each being engaged with one of the plurality ofmagnetic driving rotors, such that each motor individually drives therotation of one of the magnetic driving rotors.

In some embodiments, and without limitation, the present inventionrelates to a magnetically driven conveyor system, comprising at leastone barrier; a plurality of passive magnetic rotors on a first side ofthe barrier; and a plurality of magnetic driving devices located on asecond side of the barrier for magnetic engagement with the plurality ofpassive magnetic rotors across the barrier, where the magnetic drivingdevices drive the rotation of the passive magnetic rotors. The systemmay include at least one motor for driving the rotation of the magneticdriving devices. In some examples, and without limitation, the systemmay include a plurality of motors, each being engaged with one of theplurality of magnetic driving devices, such that each motor individuallydrives the rotation of one of the magnetic driving devices. In someexamples, each of the magnetic driving devices may include at least oneelectromagnet, and the magnetic driving devices may drive the rotationof said passive magnetic rotors by alternating polarity of the at leastone electromagnet.

In some embodiments, and without limitation, the present inventionrelates to a method of conveying items on a roller conveyor system thatincludes using a motor to pull a driving chain and rotate a plurality oftransmission assemblies, where the transmission assemblies each includea sprocket that is engaged with the driving chain; magnetically drivinga plurality of passive magnetic rotors that are each attached to one ofa plurality of rollers, where each of the plurality of transmissionassemblies includes a magnetic driving rotor that rotates with thesprocket and is magnetically engaged with one of the plurality ofpassive magnetic rotors across a barrier; and rotating the plurality ofrollers through a fixed attachment of each of the plurality of rollersto one of the passive magnetic rotors. Each of the passive magneticrotors may be embedded in an end of one of the plurality of rollers suchthat there is little to no protrusion of the passive magnetic rotor fromthe end of the roller.

In some embodiments, and without limitation, the present inventionrelates to a method of conveying items on a conveyor system, comprisingusing a motor to drive the rotation of a magnet driving rotor, androtating a passive magnetic rotor through the magnetic coupling of themagnet driving rotor and the passive magnetic rotor, wherein the passivemagnetic rotor and the driving magnetic rotor are separated by a barrierand there is no physical connection between the passive magnetic rotorand the driving magnetic rotor. The passive magnetic rotor may beconnected to a roller in a conveyor bed, and the rotation of the passivemagnetic rotor may rotate the roller. In some examples, the systemcomprises a plurality of magnetic driving rotors, a plurality of passivemagnetic rotors, and a plurality of rollers positioned in said conveyorbed for advancing items along said conveyor bed. The magnetic drivingrotors may be driven by a single motor/drive chain arrangement, in whicheach magnetic driving rotor includes a transmission assembly that isengaged with and is rotated by the drive chain. In other examples, thesystem may include a plurality of motors, each of the plurality ofmotors being engaged with one of the plurality of magnetic drivingdevices.

It is an object of the present invention to provide a sanitary conveyingsystem that minimizes the accumulation of contaminants and debris withinthe conveyor bed.

It is also an object of the present invention to provide a conveyingsystem that includes no physical connections between rollers in theconveyor bed and the mechanism for driving the rotation of the rollers.

It is also an object of the present invention to provide a conveyingsystem having rollers that are magnetically engaged with a drivingsystem for rotating the rollers, where the driving system is on theopposite side of a retaining wall (sidewall) that runs along the lateralsides of the conveyor bed.

It is also an object of the present invention to provide a conveyorsystem in which the rollers that are in close proximity to a sidewall ofthe conveyor bed such that there little to no gap between the outersurface of the roller (e.g., a cylindrical brush) and the sidewall.

It is also an object of the present invention to provide a conveyorsystem for washing and waxing applications for fruit and other producein which there is little to no gap between the lateral end of therotating brushes or rollers and the sidewall (sidewall) of the conveyorbed, such that bacteria and other contaminants and other debris do notaccumulate between the roller brushes and the sidewall.

It is an object of the present invention to provide a sanitary conveyorfor use in produce processing that requires less cleaning, allowing forlonger continuous operation times and higher efficiency.

It is an object of the present invention to provide a sanitary conveyorwhich is quickly and easily broken down for cleaning.

Additional aspects and objects of the invention will be apparent fromthe detailed descriptions and the claims herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a conveyor system according to anembodiment of the present invention.

FIG. 2 is a perspective view of a conveyor system according to anembodiment of the present invention, wherein the supporting legs of theframe have been cropped to allow for a closer view.

FIG. 3 is a perspective view of a conveyor system according to anembodiment of the present invention, wherein the supporting legs of theframe have been cropped to allow for a closer view.

FIG. 4 is an overhead, close-up view of a conveyor bed according to anembodiment of the present invention in which the magnetic driving rotorsare retracted from the sidewall of the conveyor bed, wherein thestructures other than the rollers, passive magnetic rotors, magneticdriving rotors, and transmission assemblies have been cropped to allowfor a closer view.

FIG. 5 is a perspective view of a roller according to an embodiment ofthe present invention.

FIG. 6 is a perspective view of a conveyor system according to anembodiment of the present invention, in which the arrangement of aroller and a passive magnetic rotor are shown through a transparentrepresentation of the first roller, and the supporting legs of the framehave been cropped to allow for a closer view.

FIG. 7 is a perspective view of a conveyor system according to anembodiment of the present invention, in which the arrangement of passivemagnetic rotors, magnetic driving rotors, and transmission assemblies isshown, and certain structures have been cropped to allow for a closerview, including the sidewall, portions of the frame and some of therollers, magnetic driving rotors and transmission assemblies.

FIG. 8 is a frontal, close-up view of a passive magnetic rotor accordingto an embodiment of the present invention, in which passive magneticrotor has a plurality of magnets having an alternating pattern ofpolarities.

FIG. 9 is a perspective, close-up view of a conveyor system according toan embodiment of the present invention, in which the arrangement ofpassive magnetic rotors, magnetic driving rotors, and transmissionassemblies is shown, and the alignment of magnets between the passivemagnetic rotors and the driving magnetic rotors is shown, with one ofthe magnetic driving rotors shown as transparent. Certain structureshave been cropped to allow for a closer view.

FIG. 10 is a perspective view of a conveyor system according to anembodiment of the present invention, in which the arrangement oftransmission assemblies and a driving chain is shown, wherein thesupporting legs of the frame have been cropped to allow for a closerview.

FIG. 11 is a perspective view of a conveyor system according to anotherembodiment of the present invention, in which the arrangement oftransmission assemblies and a sinusoidal driving chain is shown, whereinthe supporting legs of the frame have been cropped to allow for a closerview.

FIG. 12 is a perspective, close-up view of a conveyor system accordingto an embodiment of the present invention, in which an exploded view ofa transmission assembly is shown. Certain structures have been croppedto allow for the close-up view.

FIG. 13 is a perspective view of a conveyor system according to anotherembodiment of the present invention, in which the driving magneticrotors are electromagnetic, wherein the supporting legs of the framehave been cropped to allow for a closer view.

FIG. 14 is a perspective view of a conveyor system according to anotherembodiment of the present invention, in which the driving magneticrotors are electromagnetic, wherein the supporting legs of the framehave been cropped to allow for a closer view.

FIG. 15 is a frontal, close-up view of an electromagnetic driving rotor(stator) according to an embodiment of the present invention.

FIG. 16a is an overhead, close-up view of an arrangement of passivemagnetic rotors and magnetic driving rotors, in which the passivemagnetic rotors are suspended in the conveyor bed by magnetic attractionto the magnetic driving rotors. Certain structures have been cropped toallow for the close-up view.

FIG. 16b is an overhead, close-up view of an arrangement of passivemagnetic rotors and magnetic driving rotors, in which the passivemagnetic rotors are suspended in the conveyor bed by an axial pininserted into a recess in a sidewall of the conveyor bed. Certainstructures have been cropped to allow for the close-up view.

FIG. 16c is an overhead, close-up view of an arrangement of passivemagnetic rotors and magnetic driving rotors, in which the passivemagnetic rotors are suspended in the conveyor bed by an axial pinpassing through a hole in a sidewall of the conveyor bed. Certainstructures have been cropped to allow for the close-up view.

FIG. 17 is a perspective view of a conveyor system according to anembodiment of the present invention, in which a sweeping device isshown. Certain structures have been cropped to allow for a clearer viewof the sweeping device and related structures.

FIG. 18 is a side view of a conveyor system according to an embodimentof the present invention, in which a sweeping device is shown and thesidewall is shown as transparent to allow a view of the sweeping device.Certain structures have been cropped to allow for a clearer view of thesweeping device and related structures.

DETAILED DESCRIPTION

Reference will now be made in detail to certain embodiments of theinvention, examples of which are illustrated in the accompanyingdrawings. While the invention will be described in reference to theseembodiments, it will be understood that they are not intended to limitthe invention. To the contrary, the invention is intended to coveralternatives, modifications, and equivalents that are included withinthe spirit and scope of the invention as defined by the claims. In thefollowing disclosure, specific details are given to provide a thoroughunderstanding of the invention. However, it will be apparent to oneskilled in the art that the present invention may be practiced withoutthese specific details.

Referring to the drawings wherein like reference characters designatelike or corresponding parts throughout the several views, and referringto FIGS. 1-18, it is seen that the present invention includes variousembodiments of a conveyor bed having a magnetic rotor system for drivingrollers in the conveyor bed.

The conveyor systems of the present invention may include a roller bedhaving a generally linear conveying path with a plurality of rollersarranged in a parallel fashion such that the rollers are generallylongitudinally parallel. However, it should be understood that in someexamples, and without limitation, the roller bed may have a curved orpartially curved, or multi-directional conveying path such that all or aportion of the rollers are not parallel to each other and some or all ofthe rollers may be at an angle relative to an adjacent roller. Theconveying system may have sidewalls that run parallel to the path of theconveying system for retaining produce or other items on the conveyor.On an exterior side of at least one of the sidewalls, the conveyorsystem may include a plurality of transmission assemblies, each of thetransmission assemblies being engaged with a magnetic driving rotorassociated with one of the rollers and magnetically coupled to theroller. The conveyor system may also include one or more motors fordriving the rotation of the magnetic driving rotors, and the one or moremotors may be connected to the transmission assemblies by a chain orbelt.

The roller bed may have an input end and an output end. Produce or othermaterials or items may be deposited at the input end and travel alongthe conveying path of the roller bed towards the output end under therotary motion imparted by the motor to the rollers through thetransmission assemblies.

As an example, and without limitation, FIG. 1 shows a conveyor system 10that includes a roller bed 12 having a plurality of rollers 14. Theconveyor system 10 is exemplary of how the conveying systems of thepresent invention may be designed and operate, but it should beunderstood that the conveying systems of the present invention may bemuch larger (e.g., longer) and more complex than the example provided inFIG. 1. For example, conveyor system 10 may be a single module among aplurality of modules making up a larger conveying system. Variousarrangements, sizes, and implementations basic exemplary conveyor system10 are contemplated within the scope of the present invention.

The roller bed 12 is supported on a frame 30 having side walls 22 and 24to retain the produce or other items as it flows along the roller bed12. The rollers 14 may sit or be closely adjacent to the sidewalls 22and 24 of the conveyor system 10 such that there is little or no gapbetween the circumferential surface of the rollers and the sidewall andthere is little or no space in which contaminants or debris canaccumulate. Each of the rollers 14 may be magnetically connected acrosssidewall 22 to a transmission assembly 16 for driving the rotation ofthe roller. Each of the transmission assemblies 16 may be coupled to amotor 18 by a chain or belt 20. The chain or belt 20 may be connected orlooped over sprockets in each of the transmission assemblies 16, whichare discussed in more detail below.

The opposite side of each of the rollers 14 may abut or sit closelyadjacent to the sidewall 24. As shown in FIG. 2, each of the rollers 14may be supported at the sidewall 24 by a pin 40 that may be insertedinto an axial tunnel or recess in the roller 14 and also pass through acorresponding hole in the sidewall 24. The position of the pin 40 andthe roller 14 may be maintained by a collar 42 that is fixedly attachedto the pin 40 on the outer side of the sidewall 24 and that sits closelyto the sidewall 24. In some examples, and without limitation, the pin,the collar, and/or the end of the roller near or abutting the sidewallmay be made from or coated with a low friction material in order toprevent drag and resistance to the rotation of the rollers duringoperation of the conveying system. The lateral side of the conveyorsystem that includes the sidewall 24, and the pin and collar assembliesmay be a passive side of the conveyor system with no driving mechanism.

In other embodiments, and without limitation, the rollers 14 may besupported by a pin that does not traverse the sidewall 24 on the passiveside of the conveyor system. For example, and without limitation, eachpin 40 may be inserted into a recess 43 in the sidewall 24, as shown inFIG. 3. Recesses 43 may have a closed end into which the end of pins 40may be inserted. The pin 40 or pin end and the interior of the recesses43 may be made from or coated with a low friction material in order toprevent drag and resistance to the rotation of the rollers duringoperation of the conveying system. In some implementations, and withoutlimitation, a bearing assembly may be present in the recess to reducefriction between the pins 40 and the recesses 43. Such embodiments mayallow for the quick disassembly of the system for cleaning, without theneed to disengage a collar or other structure before removing the pin 40from sidewall 24. Also, such embodiments may help reduce thecontamination of the conveyor bed components by passage of contaminantsacross the sidewalls.

The magnet coupling arrangement of the passive magnetic rotors on theother side of the conveyor bed may allow for easy access to anddisassembly of the components of the system for maintenance andcleaning. In some embodiments, and without limitation, the rollers maybe disengaged from the roller bed for washing by removing the pin andcollar on the passive side of the conveyor system (or, alternatively,simply pulling them from recesses 43). After removing the pin and collarassemblies, the rollers may be disengaged from the magnetic drivingrotors by retracting them away from the sidewall, as shown in FIG. 4.FIG. 4 shows the magnetic driving rotors 17 retracted away from thesidewall 22 creating a gap 25 between the magnetic driving rotors 17 andthe sidewall 22, such that the magnetic attraction between the drivingmagnetic rotors and the passive magnetic rotors is diminished, and therollers 14 may be removed from the conveyor bed. The rollers (includingthe passive magnet rotors) and the retaining walls may then be washedand disinfected. No cleaning procedure may be necessary for the drivingsystem (e.g., aside from general motor and transmission maintenance)because it may be completely isolated from the interior of the rollerbed, preventing the passage of debris and contaminants from the rollerbed into the driving system. In other embodiments, and withoutlimitation, the conveyor system may include a mechanism for spreadingthe conveyor bed, e.g., by increasing the distance between the sidewallsto thereby provide room and access to remove the rollers and distancebetween the passive magnetic rotors and the driving magnetic rotors toreduce the magnetic attraction. In still further embodiments, andwithout limitation, the magnetic driving rotors may have electromagnetsrather than permanent magnets, and the rollers may be removed by simplyturning off the electromagnets, and thereby removing the magneticattraction between the passive magnetic rotors and the driving magneticrotors.

The rollers of the conveyor system may be of uniform length anddiameter, and they may be positioned in a parallel arrangement such thatthe axes of the rollers are about perpendicular to the path of theconveyor bed. FIGS. 5-6 provide views of exemplary rollers according tothe embodiments of the present invention. In some embodiments, therollers 14 may have a slot, hole, or tunnel (e.g., a cylindrical tunnel)running down the axial center thereof, which may receive all or aportion of a passive magnetic rotor assembly. The slot, hole, or tunnelallows the passive magnetic rotor assembly to be embedded in the rollersuch that the outer diameter of the roller may abut or sit within ashort distance of the sidewall (e.g., about 1 mm to about 5 mm, or anyvalue or range of values therein). In some implementations, and withoutlimitation, the roller may have two recesses of different diameters forallowing all or nearly all of the passive magnetic rotor to be embeddedin the roller. For example, the roller may include an axial tunnel forreceiving an axial anchor of the passive magnetic rotor (see, e.g.,cylindrical anchor 15 c in FIG. 6), and an outer recess having a greaterdiameter for receiving the body of the passive magnetic rotor (see,e.g., disk 15 b in FIG. 6). The dual recess may allow the entire passivemagnetic rotor to be embedded in the end of the roller.

As an example and without limiting the invention, FIG. 5 shows anexemplary roller 14 having a cylindrical shape and with two lateral ends14 a and 14 b, an outer circumferential surface 14 c, and a tunnel 14 drunning down the axial center of the roller 14. The cylindrical tunnel14 d may have a shape that accommodates a passive magnetic rotorassembly such that the passive magnetic rotor assembly sits completelyor nearly completely within the roller 14.

Without limiting the invention, FIG. 6 shows a transparent view of anexemplary roller 14 t installed in a conveyor system 10. The passivemagnetic rotor 14 t can be seen engaged with an end of the roller 14 t.The passive magnetic rotor 14 t may include a disk 15 b in which acircumferential arrangement of recesses 15 a may be formed. Circularmagnets may be embedded in the recesses 15 a on the outer side of thepassive magnetic rotor. The passive magnetic rotor 15 may also include acylindrical anchor 15 c for engaging with the tunnel 14 d of the roller14 t. The anchor 15 c may fit snuggly within the tunnel 14 d such thatthe relative positions of the passive magnetic rotor and the roller arefixed. The passive magnetic rotor assembly may also sit flush in theroller such that the outer circumferential surface of the passivemagnetic rotor and is flush with the outer circumferential surface ofthe roller, and thus little or no gap may be formed between the rollerand the sidewall of the conveyor system. The passive magnetic rotorassembly may also have a snug fit to prevent slipping between thepassive magnetic rotor assembly and the roller. In some examples, andwithout limitation, the tunnel may include one or more grooves, notches,or other recesses or protrusions running down its length. The passivemagnetic rotor assembly may in turn have a portion having protrusions orrecesses that complement the shape of the recesses or protrusions in thetunnel.

In some examples, and without limitation, the rollers may have an axiallength in a range from about one foot to about 8 feet (e.g., about twofeet to about six feet, or any value or range of values therein). Insome examples, and without limitation, the rollers may have a diameterin a range from about two inches to about one foot (e.g., about threeinches to about eight inches, or any value or range of values therein),depending on whether the roller includes any protrusions on its outersurface and the length of the protrusions thereon.

Each of the rollers of the conveyor system may include an outer brushportion that may have protrusions, fibers, filaments, or pegs thereon.For example, and without limitation, the brushes may include providebristles over the some or all of the roller surface, e.g., in particularpatterns on the roller. In other examples, and without limitation, thebristles may be provided in separate longitudinal rows, circumferentialrows, spiral rows, patches, etc. The fibers, filaments, or bristles ofthe brush may be made from various polymer materials (e.g., polyamides,polystyrene, polyester, polyolefin, polypropylene, polyurethane,polyvinylidene chloride, polyethylene, etc.; copolymers thereof; nylon;or other materials) in a flexible fiber form. In other embodiments, andwithout limitation, the fibers, filaments, or bristles may include othermaterials. The fibers, filaments, or bristles may have sufficientrigidity that they flex under the weight of a piece of produce (e.g., anapple, strawberry, tomato, etc.) or other items, but they support theweight of the produce or other items and do not collapse such that theproduce lies against the roller. In some implementations, and withoutlimitation, the conveyor system of the present invention may beconfigured for washing produce, in which case the roller surfaces mayhaving relatively short, firm bristles (e.g., in a range of about 1 mmto about 20 mm, or any value or range of values therein) that do nottrap excess water sprayed onto the conveyor for cleaning purposes. Theprotrusions on the surface of the roller may be spaced and shaped suchthat they can be thoroughly washed to remove any contaminants that mayaccumulate thereon during operation of the system. In further examples,and without limitation, the rollers may have a smooth and/or tacky outersurface that is both washable and capable of moving the produce or othermaterials along the conveyor.

The passive magnetic rotor assemblies may be mechanically coupled to therollers of the conveying system, as described above, and they may alsobe magnetically coupled to magnetic driving rotors that are incorporatedinto the transmission assemblies and located on the outside of theconveyor bed (e.g., an outer side of one of the sidewalls of theconveyor system). The passive magnetic rotor assemblies may bemagnetically coupled to the magnetic driving rotors across the sidewallof the conveyor system, and thus the sidewall may be a non-magneticmaterial and sufficiently thin to allow the magnetic driving rotors tomagnetically engage the passive magnetic rotors on the opposite side ofthe sidewall with sufficient attractive force to drive the rotation ofthe rollers. For example, and without limitation, the sidewall may bemade from one or more non-magnetic, rigid, and sturdy materials such asstainless steel, ceramic, polymer, composite, etc. The sidewall may havea thickness in a range of about 0.5 mm to about 10 mm (or any value orrange of values therein).

As an example and without limitation, FIG. 7 provides a view of anexemplary arrangement of the rollers 14 and the transmission assemblies16 across the sidewall, in which the sidewall is transparent to allow anunobstructed view of the rollers 14. Each of the rollers 14 may bealigned with a transmission assembly 16. The passive magnetic rotorassemblies 15 are shown embedded in the end of the rollers 14, asdiscussed above. On the opposite side of the sidewall (not shown) themagnetic driving rotor 17 may be abutting or closely adjacent to thesidewall and may be aligned with the corresponding passive magneticrotor on the opposite side of the sidewall.

Both the passive magnetic rotor and the magnetic driving rotor may havea plurality of magnets therein. The magnetic rotor may have a pluralityof small magnets embedded in the interfacing surface thereof, whereinsaid magnets are arranged such that the polarity of the magnetsalternate between adjacent magnets on the interfacing surface. Forexample, FIG. 8 shows the interfacing surface of a magnetic drivingrotor 17 having a circular pattern of disk magnets 17 a near thecircumference of the magnetic driving rotor 17, and the polarity of theoutward facing surface of these magnets may alternate between north andsouth from magnet to adjacent magnet. The passive magnetic rotor mayhave a complementary pattern of magnets, such that the magnets of thepassive magnetic rotor stay aligned with the oppositely poled magnets ofthe magnetic driving rotor as the magnetic driving rotor spins becausethe magnets of the passive magnetic rotors are simultaneously attractedby the oppositely poled magnets of the magnetic driving rotor with whichthey are aligned and repelled by the adjacent like-poled magnets of themagnetic driving rotor. For example, FIG. 9 shows an alignment ofpassive magnetic rotors 15 embedded within rollers 14 having a pluralityof small disk magnets 15 a embedded in the faces thereof, where thepolarity of the magnets 15 a alternate between north and south, and eachof the magnets 15 a is aligned with a corresponding magnet 17 a of theopposite polarity in the face of the corresponding magnetic drivingrotor 17. The sidewall 22 and one of the magnetic driving rotors 17 aretreated as transparent (not shown) in FIG. 9 so that the alignment ofthe magnets 15 a and 17 may be clearly shown.

In other examples, and without limitation, the magnet driving rotor mayhave magnets arranged such that polar orientations of the magnets allmatch each other (e.g., the positive poles may all be facing outwardfrom the face of the rotor), and the passive magnetic rotor may have itsmagnets arranged with matching polar orientations, such that theypolarity of the outer face (the interfacing surface) of the magnets isopposite to the outer face of the magnets of the magnetic driving rotorand the rotors are attracted to one another (e.g., the negative polesmay all be facing outward from the face of the rotor). In still furtherexamples, and without limitation, the magnet driving rotor may havemagnets arranged such that the polar orientation of the magnets are thesame, and the passive magnetic rotor may have its magnets arranged suchthat the polar orientations are the same and they match the orientationof the magnets in the magnetic driving rotor such that the magneticdriving rotor repels the passive magnetic rotor. The repulsion of thepassive magnetic rotor may cause it to spin away from alignment with themagnetic driving rotor, and as the magnetic driving rotor spins it maydrive the passive rotor to spin by repulsion. In such embodiments, andwithout limitation, the passive magnetic rotors may each be suspendedand held in position and in alignment with the corresponding magneticdriving rotors by an axial pin or rod in the rollers that engages with arecess or opening in the sidewall.

In still further embodiments, and without limitation, the magneticdriving rotor may include two semicircular magnets of opposite polarityrunning along the perimeter of the magnetic driving rotor, and thepassive magnetic rotor may have a complementary arrangement ofsemicircular magnets, such that the magnets experience the sameattraction and repulsion forces as described in the above example. Inyet further embodiments, the passive magnetic rotor may have a circularmagnet along or near its circumference having a first polarity and themagnetic driving rotor may have a circular magnet having substantial thesame size as the magnet in the passive magnet rotor, but having anopposite polarity. Various other arrangements of magnets on the passivemagnetic rotors and magnetic driving rotors are contemplated within thescope of the present invention. For example, the magnets in the passivemagnetic rotors do not necessarily have the same size and shape as themagnets in the magnetic driving rotor. Additionally, the passivemagnetic rotors and the magnetic driving rotors do not necessarilyinclude permanent magnets therein. For example, and without limitation,the magnetic driving motors may include electromagnets.

The transmission assemblies of the present invention provide aconnection between the magnetic driving rotors and a motor. Thetransmission assemblies may include an axle nested within one or morebearings to provide a stable rotating structure, and a sprocket whichmay be connected to a chain or belt that is rotated by a motor. Thechain or belt may be connected to a series of sprockets, each being apart of an individual transmission assembly. As an example, and withoutlimiting the invention, FIG. 10 provides a similar view to that of FIG.1 with the sidewall 22 shown intact and a driving chain 20 engaged withthe sprockets 16 d. A plurality of transmission assemblies 16 are shownon the exterior side of sidewall 22, each having an axle 16 a, bearings16 b and 16 c, and a sprocket 16 d. The driving chain 20 may be engagedwith the teeth of each of the sprockets 16 d such that the sprockets arerotated by the driving chain as the drive shaft of the motor 18 rotatesone of the driving magnetic rotors 16 (e.g., an end rotor) and thesprocket 16 d of the end rotor, in turn, cycles the chain 20. The motormay be a servo motor, AC motor, or other electric motor that rotates anaxle with which the sprocket of the end rotor is engaged. In otherembodiments, and without limitation, the motor may be engaged with thechain directly and the chain may drive the rotation of all of themagnetic driving rotors. The driving chain 20 may be engaged with theteeth of the sprockets and may sit substantially horizontally above andbelow the sprockets, engaging with only the superiorly and inferiorlypositioned teeth of the sprockets (except in the case of the endsprockets, which the drive chain may wrap around). In otherimplementations, the conveyor path may have a pitch angle relative to ahorizontal plane (e.g., an ascending or descending conveyor path), andthe rollers, transmission assemblies, and driving chain may run along orparallel to the conveyor path.

In still other implementations, and without limitation, the conveyorsystem may have passive gears or other structures between the sprocketsthat may change the path of the chain such that the driving chainengages with more teeth of each sprocket and engages with a greaterportion of the circumference of each of the sprockets. The increasedengagement of the driving chain with the sprockets may provide improvedenergy transfer efficiency between the motor and the sprockets. Forexample, and without limitation, FIG. 11 shows an implementation of theconveyor system 10 in which the driving chain 20 is engaged with boththe teeth of the sprockets 16 d and passive gears 27. The passive gears27 sit between adjacent sprockets and closer to the horizontal plane onwhich the axles 16 a are aligned, such that the driving chain has asinusoidal path and engages with more teeth of the sprockets 16 d thanthe chain in embodiments like that shown in FIG. 10.

Without limiting the invention, FIG. 12 provides an exemplaryarrangement of a transmission assembly and a magnetic driving rotoraccording to an embodiment of the present invention. One of thetransmission assemblies 16 and the associated magnetic driving rotor 17are shown in an exploded view. In this example, it can be seen that theaxle 16 a may pass through central passages in each of the bearings 16 band 16 c, the sprocket 16 d, and the magnetic driving rotor 17 such thatthe passages in these structures are concentric. The sprocket and themagnetic driving rotor may be in a static relationship, being fixedlyengaged to one another, such that the magnetic driving rotor spins withthe sprocket. The fixed relationship of the sprocket and the magneticdriving rotor may result from direct attachment of the sprocket to themagnetic driving rotor (e.g., by one or more, bolts, pins, or otherfasteners) and/or an interlocking engagement of the sprocket and themagnetic driving rotor with the axle (e.g., the axle may have one ormore slots, protrusions, or other engagement structures, and the centralpassages of both the sprocket and the magnetic driving rotor may haveengagement structures that are complementary to the engagementstructures of the axle).

Although the presented exemplary embodiments include a sprocket andchain transmission system, there are substitutions and modificationsthat may be made to the driving system described herein, and suchsubstitutions and modifications are within the scope of the presentinvention. For example, each shaft could be coupled to its next adjacentshaft by passive gears rather than by a chain or belt.

In some embodiments, and without limitation, each of the magneticdriving rotors may be engaged with a separate motor. For example, eachmagnetic driving rotor may be connected to and driven by its own ACmotor, a servo motor, etc. FIG. 13 shows an exemplary embodiment inwhich each magnetic driving rotor 17 is engaged with a separate motor 70for driving the rotation of the magnetic driving rotor. The axle of eachmotor 70 may be directed connected or indirectly connected via acoupling device to one of the magnet driving rotors 17. The motors 70may be in electronic communication with a controller. The controller mayhave analog or digital controls for turning the motors on or off, and/orto set a rate at which the magnetic driving rotors spin. In someexamples, and without limitation, the controller may be in electroniccommunication with a computer or processing unit (e.g., a system havinga microprocessor), which may positioned at or near the conveyor bed ormay be remote and have a wired or wireless connection to the controller.Such a computer or processing unit may include software capable ofdirecting the controller to signal the motors to drive rotation of thedriving rotors at various speeds.

Without limitation, the driving system may incorporate electromagnets insome embodiments of the present invention. In some embodiments, andwithout limitation, rather than having a motor and a driving belt orchain, the magnets in the face of the driving magnetic rotor may beelectromagnets connected to an electronic control circuit. In someexamples, each of the driving magnetic rotors and the passive rotors mayact together like a brushless DC motor, in which a control circuit mayalternate the application of direct current to electromagnetic coilswithin the magnetic driving rotor (which is an electromagnetic stator insuch embodiments) to generate a moving magnetic field that may rotatearound the magnetic driving rotor as current is successively deliveredin a coordinated manner from coil to coil. As an example, and withoutlimitation, FIG. 14 shows an embodiment of the present invention thatincludes electric motors 80 that drive the rotation of the passivemagnetic rotors by utilizing a circular arrangement of electromagnets asan electromagnetic stator. FIG. 15 shows an electromagnetic drivingrotor 117 (really a stator), which may be located within each of theelectric motors 80. The driving rotor 117 includes multiple coils 117 ato which a controller may deliver current in a circulating pattern. Forexamples, the control circuit may first deliver current to the uppermost coil and then switch the delivery of current in a clockwisedirection from one coil to the next to create a circular movement of themagnetic field. This circular magnetic field may interact with one ormore permanent magnets in the interfacing surface of the passivemagnetic rotor, thereby causing the passive magnetic rotor to spin andcause the roller in which it is embedded to rotate. The speed at whichthe direct current is switched between coils in the electromagneticdriving rotor 117 determines the speed at which the passive magneticrotor rotates. In other embodiments, and without limitation, the controlcircuit may deliver current to each coil simultaneously and the polarityof the magnets may be controlled such that adjacent magnets always haveopposite polarities. Additionally, the passive magnetic rotor may havepermanent magnets arranged in a pattern that corresponds (e.g., themagnets have the similar size and placement) to the pattern ofelectromagnets in the electromagnetic driving rotor, where the permanentmagnets alternate in polarities such that adjacent magnets have oppositepolarities. In such a design, the current delivered to each coils may bereversed back and forth (positive to negative and vice versa) in orderto alternate the polarity of the electromagnet. The alternation of thepolarity of the electromagnets may propel rotation of the passive rotoras the polarities of each of the electromagnets alternate in acoordinated pattern. The speed of the rotation of the passive magneticrotor (and the roller) may be controlled by the frequency of thereversing current applied to the electromagnets.

In such embodiments and without limitation, the conveyor system mayinclude a processing unit (e.g., an IC processor) that is in electroniccommunication with the control circuit and is operable to monitor andcontrol the rotational speed of the magnetic driving rotors. Themagnetic driving rotors may include sensors (e.g., Hall-effect sensors)therein that detect magnetic fields therein that are in electroniccommunication with the processing unit. One or more magnetic fieldsensors may be positioned between the coils. The sensors may detect thelocation of the magnetic poles of the permanent magnets on the passivemagnetic rotor as the passive magnetic rotor rotates. Using the dataprovided by the magnetic field sensors, the processing unit maydetermine which coils to activate to optimize the spin of the passivemagnetic rotors. The processing unit may also be programmed to maintaina predetermined rotational speed or vary the rotational speed accordingto a predetermined pattern. The predetermined rotational speed orvarying speed pattern may be selected by the operator of the system fromexisting programming (e.g., from a set of predetermined selectablesettings provided in firmware and/or software of the processing unit) ormay be programmed and set by the operator using an operator interfaceoperable to allow the operator to program rotational speeds and patternsof variable rotational speeds within a range of available rotationalspeeds.

The present invention is intended to reduce or eliminate the passage ofmaterials from the interior of the conveyor bed to the exterior and viceversa. In some embodiments, and without limitation, the sidewall 22 mayhave no holes therein in order to prevent the passage of debris andcontaminants from the conveyor bed to the area of the driving system anddamage to the driving system components (e.g., the transmissionassemblies, the driving chain or belt, the motor, etc.). In suchimplementations, the magnetic driving rotor may act to suspend andmaintain the position of the corresponding passive magnetic rotor (andthe roller) on the opposite side of the sidewall, such that no axle orpin is required to position the roller. Such an arrangement is shown inFIG. 16a . In FIG. 16a , sidewall 22 is shown as transparent todemonstrate that there is no pin or rod for suspending the rollers 14 inposition, and no recesses or holes in sidewall 22 for receiving suchrods or pins. FIG. 16a also shows that rollers 14 may each include agasket 60 that abuts the sidewall 22 to prevent or reduce the movementof debris from the interior of the conveyor bed into the area betweenthe roller 14 and the sidewall 22.

In other embodiments, and without limitation, the sidewall may have arecess (that does not pass completely through sidewall) for receiving apin or an axle of the roller. In such implementations, each recess mayreceive a pin or rod protruding from a roller, and aid in suspending theroller within the conveyor bed. As shown in FIG. 16b , the sidewall 22(depicted as transparent) may have recesses 61 therein for receivingaxial pins 62 from the rollers 14. The rollers 14, the axial pins 62,the recesses 61, and the magnetic driving rotors 17 may all beconcentric, allowing for efficient rotation of the rollers. FIG. 16bdoes not show a gasket 60 that abuts the sidewall 22 in order to showthe position of the axial pin 62. However, it should be noted that theembodiment may include the gasket 60 (see FIG. 16a for reference).

In still other embodiments, and without limitation, the sidewall mayhave a hole for receiving a pin or an axle of the roller. In suchimplementations, a grommet or gasket may encircle each hole and the pintherein to prevent the transfer of debris across the sidewall. As shownin FIG. 16c , the sidewall 22 (depicted as transparent) may have holes63 therein to allow the passage of axial pin 62 through sidewall 22 sothat they can engage with the magnetic driving rotors 17. The axial pinmay aid in keeping the roller and/or the magnetic driving rotor instable, predetermined position and maintain the proper alignment betweenthe magnetic driving rotor and the passive magnetic rotor on theopposite side of the sidewall 22. FIG. 16c also shows grommets 63 thatsurround the axial pin at the holes in the sidewall 22. FIG. 16c doesnot show a gasket 60 that abuts the sidewall 22 in order to show theposition of the axial pin 62. However, it should be noted that theembodiment may include the gasket 60 (see FIG. 16a for reference).

In some embodiments, and without limitation, the conveyor system of thepresent invention may also include a sweeping device or clean-out barthat may be used to periodically clear produce or other items from theconveyor bed. The sweeping device include a sweeping bar that can bepassed closely over the rollers of the conveyor bed from the input endof the conveyor bed to the output end, drawing any produce or otheritems or materials off of the rollers and out of the conveyor bed. Likethe rollers of the conveyor system, the sweeping device may be connectedto an exterior driving mechanism by magnetic force. As an example, andwithout limitation, FIGS. 17-18 show a sweeping device system 50 forclearing produce or other items off of a conveyor bed. The conveyor bedand rollers are absent from FIG. 17-18 drawings for the sake of visualclarity. The sweeping device may include a driving system that may be onthe exterior side of one or both of the sidewalls of the system and asweeping arm that is connected to the driving system by magnetic forceacross the sidewall.

For example, and without limitation, FIGS. 17-18 show a sweeper drivingsystem on an exterior side of sidewall 24 that includes a motor 55 thatdrives a sprocket 56, which is connected to a driving bar that drives asecond sprocket 58 on an outer side of sidewall 22. The driving systemincludes two driving belts or chains 54 (sidewall 22 obscures the viewof the second driving belt on the outer side thereof) that have magneticcouplers 53 attached thereto. As the motor 56 rotates the sprocket 55,the driving belts or chains rotate and move magnetic couplers 53 in anoblong path over the conveyor bed. The magnetic couplers 53 engage withmagnetic couplers 52 across the sidewalls. A sweeping bar 51 is attachedto the magnetic couplers 52 and is moved along the oblong path of thedriving belts or chains as they rotate. The sweeping bar 51 ispositioned such that it passes closely over the rollers in the conveyorbed for about half of its path. During the remaining portion of itspath, the sweeping bar is inverted away from the conveyor bed and ispassed back to the input end 100 of the conveyor system 10 so that itcan make another pass over the conveyor bed. As the driving belt orchain is rotated on the sprocket, it may draw the sweeping bar along theconveyor bed and push produce or other items toward the output end 200of the conveyor system. Other implementations and designs of thesweeping device are contemplated within the scope of the presentinvention.

In operation, produce or other items may be fed into the input end ofthe conveyor system by human operators or from another conveyor orprocessing system. The roller conveyor may propel the produce along theconveyor bed as the rollers rotate. The motor and driving system may beoperated at different speeds to drive the rotation of the rollers atdifferent rotational speeds for different operations. The conveyorsystem may include additional components that are necessary forparticular operations. For example, the conveyor system may include oneor more spray nozzles for spraying water, cleaning solutions, and/or waxover the produce that is loaded onto the conveyor bed. The produce orother items may travel along the conveyor bed to the output end of theconveyor where the produce or other items may be transferred to anotherprocessing device (e.g., another conveyor, a sorting or sizing table,etc.).

The present invention provides novel conveying systems that use magneticcoupling across a barrier between transmission assemblies of a drivingsystem and rollers in a conveyor bed. The arrangement of the passivemagnet rotors and the magnetic driving rotors allows for a gapless ornearly gapless roller bed that prevents or reduces the accumulation ofdebris and contaminants in the hardware of the conveyor system. Thesanitary conveyors of the present invention may be advantageously usedin produce processing and other applications with reduced cleaning andmaintenance requirements, allowing for longer continuous operation timesand higher efficiency.

It should be understood that the foregoing descriptions of specificembodiments of the present invention have been presented for purposes ofillustration and description. They are not intended to be exhaustive orto limit the invention to the precise forms disclosed, and obviouslymany modifications and variations are possible in light of the aboveteachings. The embodiments were chosen and described in order to bestexplain the principles of the invention and its practical application,and to thereby enable others skilled in the art to best utilize theinvention and various embodiments with various modifications as aresuited to the particular use contemplated.

What is claimed:
 1. A conveying system assembly, comprising: a. aconveyor bed for holding rollers, b. a plurality of rollers in saidconveyor bed, c. at least one lateral sidewall positioned longitudinallyalong said conveyor bed, d. at least one magnetic driving device locatedoutside of said conveyor bed and adjacent to an outer side of said atleast one lateral sidewall, and e. at least one passive magnetic rotor,wherein said at least one passive magnetic rotor is located inside ofsaid conveyor bed and adjacent to the inner side of said at least onelateral side wall, is embedded in an end of one of said plurality ofrollers, and is magnetically engaged with said at least one magneticdriving device across said at least one lateral sidewall.
 2. Theassembly of claim 1, wherein said at least one passive magnetic rotorincludes a pin that engages with a recess in an interior side of said atleast one lateral sidewall, wherein said recess does not traverse thefull thickness of the at least on lateral sidewall.
 3. The assembly ofclaim 2, wherein there are no holes in said at least one sidewalllocated at or below positions of the plurality of rollers at the atleast one lateral side wall in the conveyor bed.
 4. The assembly ofclaim 1, wherein there is little or no protrusion of said passive magnetrotor from the end of said one of said plurality of rollers.
 5. Theassembly of claim 1, wherein said at least one passive magnetic rotorsits flush against the interior side of the at least one lateralsidewall and a gap between said one of said plurality of rollers and theat least one lateral sidewall is less than about 5 mm to reduceaccumulation of debris and contaminants between said one of saidplurality of rollers and said at least one lateral sidewall.
 6. Theassembly of claim 5, further comprising gaskets between each of saidplurality of rollers and said at least one lateral sidewall to block andprevent the accumulation of any debris between the rollers and said atleast one lateral sidewall.
 7. The assembly of claim 1, wherein said atleast one magnetic driving device is retractable from said at least onelateral sidewall to allow said rollers to be removed from the assemblyfor maintenance and cleaning.
 8. The assembly of claim 1, wherein saidat least one magnetic driving device includes a plurality of magnetsarranged in a first alternating polarity pattern around the axis of saidmagnetic driving rotor.
 9. The assembly of claim 8, wherein said atleast one passive magnetic rotor includes a plurality of magnetsarranged in a second alternating polarity pattern around the axis ofsaid passive magnetic rotor.
 10. The assembly of claim 9, wherein saidfirst alternating polarity pattern and said second alternating polaritypattern are complementary and are aligned across said sidewall, suchthat each of the negative poles in said first alternating polaritypattern are aligned with one of the positive poles in said secondalternating polarity pattern and each of the positive poles in saidfirst alternating polarity pattern are aligned with one of the negativepoles in said second alternating polarity pattern.
 11. The assembly ofclaim 1, further comprising at least one motor for driving the rotationof said magnetic driving devices.
 12. The assembly of claim 1, whereineach of said magnetic driving devices comprise at least oneelectromagnet.
 13. The assembly of claim 12, wherein said magneticdriving devices drive the rotation of said passive magnetic rotors byalternating polarity of said at least one electromagnet.
 14. A conveyingassembly, comprising: a. a conveyor bed having at least one sidewall, b.a plurality of rollers aligned in said conveyor bed on a first side ofsaid at least one sidewall, each roller having a recess in an endthereof, c. a plurality of passive magnetic rotors, each passivemagnetic rotor being embedded in said recess of one of said plurality ofrollers, and d. a plurality of magnetic driving devices located on asecond side of said sidewall for magnetic engagement with said pluralityof passive magnetic rotors across said at least one sidewall.
 15. Theassembly of claim 14, further comprising a motor, wherein said motordrives the movement of said magnetic driving devices.
 16. The assemblyof claim 14, further comprising a plurality of motors, wherein eachmotor is engaged with at least one of said plurality of magnetic drivingdevices.
 17. The assembly of claim 14, wherein each of said passivemagnetic rotors are tightly embedded in said recess of said one of saidplurality of rollers with little or no protrusion from the end of saidroller.
 18. The assembly of claim 14, wherein said passive magneticrotors sit flush against the interior side of said at least one sidewalland there is a minimal gap between said one of said plurality of rollersand said at least one lateral sidewall to reduce accumulation of debrisand contaminants between said roller and the at least one lateralsidewall.
 19. The assembly of claim 18, further comprising a gasketbetween each of said passive magnetic rotors and said at least onesidewall to further prevent the accumulation of any debris between therollers and said at least one sidewall.
 20. The assembly of claim 18,wherein a gap between each of said plurality of rollers and saidsidewall is less than about 5 mm.
 21. The assembly of claim 14, whereinsaid magnetic driving devices are retractable from said at least onesidewall, to allow said rollers to be removed from the assembly formaintenance.
 22. The assembly of claim 14, wherein each of saidplurality of magnetic driving devices includes a plurality of magnetsarranged in a first alternating polarity pattern around the axis of themagnetic driving device.
 23. The assembly of claim 22, wherein each ofsaid plurality of passive magnetic devices includes a plurality ofmagnets arranged in a second alternating polarity pattern around theaxis of the passive magnetic rotor.
 24. The assembly of claim 14,wherein each of said magnetic driving devices comprise at least oneelectromagnet.
 25. The assembly of claim 24, wherein said magneticdriving devices drive the rotation of said passive magnetic rotors byalternating polarity of said at least one electromagnet.
 26. Amagnetically driven conveyor system, comprising: a. said conveyor systemhaving a barrier; b. a plurality of rollers aligned in said conveyorsystem on a first side of said barrier, each roller having a recess inan end thereof; c. a plurality of passive magnetic rotors on said firstside of said barrier; and d. a plurality of magnetic driving deviceslocated on a second side of said barrier for magnetic engagement withsaid plurality of passive magnetic rotors across said barrier, whereinsaid magnetic driving devices drive the rotation of said passivemagnetic rotors by magnetic engagement with said passive magnetic rotorsacross said barrier.
 27. The system of claim 26, further comprising atleast one motor, wherein said motor drives rotation of said magneticdriving devices.
 28. The system of claim 27, wherein said systemincludes a plurality of motors, each motor being engaged with at leastone of said plurality of magnetic driving devices.
 29. The system ofclaim 27, wherein said magnetic driving devices include a plurality ofmagnets arranged in a first alternating polarity pattern around the axisof the rotor.
 30. The system of claim 29, wherein said passive magneticdevices include a plurality of magnets arranged in a second alternatingpolarity pattern around the axis of the rotor.
 31. The system of claim26, wherein each of said magnetic driving devices comprise at least oneelectromagnet.
 32. The system of claim 31, wherein said magnetic drivingdevices drive the rotation of said passive magnetic rotors byalternating polarity of said at least one electromagnet.
 33. The systemof claim 26, wherein each of said plurality of passive magnetic rotorsis embedded in said recess of one of said plurality of rollers.
 34. Thesystem of claim 26, further comprising at least one roller in saidconveyor bed on said first side of said barrier, said at least oneroller having one of said plurality of passive magnetic rotors in saidat least one roller.